Radioactive Spark Plugs (ca. 1940s)
The Original Idea
The idea to improve a spark plug’s performance by the use of radioactive material seems to belong to Alfred Hubbard. His patent, “Internal Combustion Engine Spark Plug” (1,723,422), was filed Feb. 11, 1924 and issued August 6, 1929. Specifically, the patent claimed that by using radium to improve the electrical conductivity of the gas, the plug could employ a larger spark gap that would result in a more complete combustion of the fuel.
Hubbard wasn’t the first to suggest that radioactive material could improve the electrical discharges between electrodes. For example, in May of 1922 Grover R. Greenslade of Pittsburgh, Pennsylvania filed a patent (1,523,013) that described the use of a radioactive material (radium, uranium, thorium and polonium) to create a conductive path between spaced electrical conductors. Although he didn’t acknowledge Greenslade, Hubbard seems to have been aware of Greenslade’s patent.
The Firestone Spark Plug
To my knowledge, the Firestone Tire and Rubber Company was the only company to market radioactive spark plugs. Firestone stopped producing them after two or three years following their introduction in 1940. Nobody else seems to have been interested in duplicating Firestone’s lack of success.
The key difference between the Firestone spark plugs and those described by Hubbard was that the Firestone plugs used polonium instead of radium as the radioactive material. The reason for doing so was spelled out in a patent taken out by John H. Dillon and assigned to the Firestone Tire and Rubber Company (Patent Number 2,254,169, filed December 1939, issued August 1941):
The polonium-210 was incorporated into the electrodes that formed the spark-gap. More specifically, the polonium was added to the molten metal (a nickel alloy) from which the wires that were used to produce the electrodes were drawn. The alpha particles emitted by the decay of the polonium would ionize the gas within the spark gap. Presumably this resulted in a longer and/or “fatter” spark.
According to Firestone’s advertising, the sparkplugs resulted in a
The November 1941 issue of the Science Digest supported this claim by citing tests that indicated
Other than the slightly improved performance when the plugs were first installed, their benefits were questionable. The short half-life of polonium-210 (138 days) meant that the enhanced performance was only temporary. It also put dealers in the uncomfortable position of having to decide what to do after unsold plugs sat on the shelf for extended periods. Furthermore, the inevitable accumulation of deposits on the surface of the plugs’ electrodes as the vehicle burned fuel would attenuate the alpha particles and prevent them from ionizing the gas.
Other Patents for Radioactive Spark Plugs
U. S. Patent No., 2128457 Alice M. Fairchild. Spark Plug. August 30, 1938 (filed December 14, 1936).
U. S. Patent No., 2,022,140. Charles Michel. Spark Plug Provided with an Ionizing Catalytic Element. November 26, 1935 (filed April 10, 1935).
U. S. Patent No., 2,457,973. Marietta Blau. Ionizing Means and Method of Ionization. January 4, 1949 (filed August 31, 1945).
Alfred Mathew Hubbard and his Atmospheric Power Generator
A simple internet search provides hours of entertaining reading about Alfred Hubbard. Rum running, LSD, CIA mind control projects – it’s all there. But for several reasons, the following discussion is limited to his atmospheric power generator. Sorry.
At eighteen, Alfred Hubbard became a public figure thanks to his invention of an “atmospheric power generator” that extracted energy from the atmosphere. Featured on the front page of the Seattle Post Intelligencer (Dec. 17, 1919), it employed no moving parts, chemicals or other type of fuel. Instead, it relied on electrical coils to convert atmospheric energy directly into electricity. Hubbard’s demonstration of the device for the newspaper article was small-scale, but impressive. The accompanying photo shows him using the coil to power a light bulb.
The following year (1920), Hubbard employed a larger version of the generator to power an 18 foot motor boat around Lake Union’s Portage Bay. Unfortunately, the cruise had to be interrupted multiple times because some of the wiring was overheating (Seattle Post-Intelligencer. July 29, 1920). Hubbard’s next demonstration project was equally dramatic, he used the coil to power an electric automobile (Monroe Monitor, Sept. 17, 1920).
Despite these successful tests, there were skeptics. After all, free electricity sounds too good to be true. And the possibility existed that Hubbard’s atmospheric power generator was part of a scam operation designed to defraud investors. Of course, that would require a corporate entity to invest in.
The Hubbard Universal Generator Company was incorporated in April of 1921. Along with Alfred Hubbard, two others were involved: William Hubbard (Alfred’s father) and Harve Phipps (the State Senator?). The three principals were certainly optimistic about their company’s prospects - it was capitalized at five million dollars! Quoting the Washington Standard (April 22, 1921):
The optimism appeared to be well placed and things seemed to progress rapidly. According to the May 18, 1921 issue of the Laurel Daily Leader:
What is odd is that the Symons-Russell Aviation Company didn’t exist – they dissolved in 1920 (Aerial Age Weekly. July 12, 1920). Of course, that would explain why Hubbard’s plane was being constructed behind closed doors.
Although he must have been busy, Hubbard continued to invent. The following note appeared in the September 23, 1921 issue of the Seattle Star:
Unfortunately, I haven’t located any information about the fate of the Hubbard Universal Generator Company, his x-ray device or the airplane project with Symons-Russell. If Hubbard was flying, he was below the radar.
It wasn’t until 1928, that Hubbard’s atmospheric power generator again drew the attention of the press. During an interview that appeared in the Feb. 26, 1928 issue of the Seattle Post-Intelligencer, Hubbard made a startling revelation:
Alas, there is no independent evidence that Hubbard worked in Pittsburgh, or had any connection with the Radium Chemical Company (RCC). However, we do have the previously mentioned newspaper accounts from April, May and September of 1921 that indicate Hubbard was living in Spokane, Washington.
His reference to “Dr. Greenslade” is particularly interesting. This could only mean Grover R. Greenslade whose patent “Method of Producing a Conductive Path Between Spaced Electrical Conductors” (1,523,013) probably served as the inspiration for Hubbard’s radioactive spark plug. Greenslade seems to have been connected to the Radium Chemical Company and might have inspired Hubbard’s claim to have worked there. Then again, if Hubbard really did work at RCC, it is reasonable that he would have encountered Greenslade.
Hubbard's statement was a bit disingenuous - it wasn’t until four or five years after the “discovery” that he claimed to have sold the 75% interest in his invention, and he supposedly did this in 1921 and 1922 while working for the Radium Chemical Company in Pittsburgh. On the other hand, the evidence that I have places him in Washington, not Pittsburgh: several newspaper accounts from 1921 indicate that he was in Spokane where he and his father incorporated the Hubbard Universal Generator Company (capitalized at $5,000,000).
When it comes to Alfred Hubbard, it can be hard to separate fact from fiction, but he sure was an interesting guy.
Alfred Hubbard. Internal-Combustion
Engine Spark Plug.
Radium Spark Plugs. Newsweek
More Efficient Spark Plugs. Science Digest November 1941, page 94.
Copyright 1999, Oak Ridge Associated Universities